/*
 * jPOS Project [http://jpos.org]
 * Copyright (C) 2000-2015 Alejandro P. Revilla
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.jpos.iso.channel;

import org.jpos.iso.*;

import java.io.IOException;
import java.net.ServerSocket;

/**
 * ISOChannel implementation - CS standard Channel<br>
 * We at <a href="http://www.cs.com.uy">CS</a>, have used
 * the so called ISOChannels for a long time. This class
 * talks with our legacy C++ based systems.<br>
 *
 * @author apr@cs.com.uy
 * @version $Id$
 * @see ISOMsg
 * @see ISOException
 * @see ISOChannel
 */
public class CSChannel extends BaseChannel {
	/**
	 * Public constructor (used by Class.forName("...").newInstance())
	 */
	public CSChannel() {
		super();
	}

	/**
	 * Construct client ISOChannel
	 *
	 * @param host server TCP Address
	 * @param port server port number
	 * @param p    an ISOPackager
	 * @see ISOPackager
	 */
	public CSChannel(String host, int port, ISOPackager p) {
		super(host, port, p);
	}

	/**
	 * Construct server ISOChannel
	 *
	 * @param p an ISOPackager
	 * @throws IOException
	 * @see ISOPackager
	 */
	public CSChannel(ISOPackager p) throws IOException {
		super(p);
	}

	/**
	 * constructs a server ISOChannel associated with a Server Socket
	 *
	 * @param p            an ISOPackager
	 * @param serverSocket where to accept a connection
	 * @throws IOException
	 * @see ISOPackager
	 */
	public CSChannel(ISOPackager p, ServerSocket serverSocket)
			throws IOException {
		super(p, serverSocket);
	}

	/**
	 * @param len the packed Message len
	 * @throws IOException
	 */
	protected void sendMessageLength(int len) throws IOException {
		serverOut.write(len >> 8);
		serverOut.write(len);
		serverOut.write(0);
		serverOut.write(0);
	}

	/**
	 * @return the Message len
	 * @throws IOException, ISOException
	 */
	protected int getMessageLength() throws IOException, ISOException {
		int l = 0;
		byte[] b = new byte[4];
		while (l == 0) {
			serverIn.readFully(b, 0, 4);
			l = ((int) b[0] & 0xFF) << 8 | (int) b[1] & 0xFF;
			if (l == 0) {
				serverOut.write(b);
				serverOut.flush();
			}
		}
		return l;
	}

	protected int getHeaderLength() {
		// CS Channel does not support header
		return 0;
	}

	protected void sendMessageHeader(ISOMsg m, int len) {
		// CS Channel does not support header
	}
}
